The present invention relates to endoscopic biopsy forceps medical devices. More particularly, the invention relates to endoscopic biopsy forceps devices having bipolar cautery capabilities.
A number of different types of endoscopic biopsy forceps devices are in common use. Ordinarily, these devices are of complicated construction, requiring the manufacturing and machining of precise miniature components, which are therefore generally quite expensive. They most often include opposing jaws for grasping and tearing tissue for biopsy. One early example of an endoscopic biopsy forceps instrument is shown in U.S. Pat. No. 3,895,636 (1975) to Schmidt, where a pair of cup shaped jaws having an annular rim which mate with a hub and a sharpened trocar is disclosed. The Schmidt device, however, does not disclose the ability to conduct cautery operations. While numerous improvements have recently been made to endoscopic biopsy forceps instruments, such as disclosed in U.S. Pat. Nos. 4,763,668 to Macek et al., 4,721,116 to Schintgen et al., 4,815,476 to Clossick, 4,817,630 to Schintgen et al., 4,880,015 to Nierman, and 4,887,612 to Esser et al., none of these patents disclose an instrument having cautery ability.
Clearly, where traumatic procedures such as taking a biopsy are being conducted, the ability to conduct endoscopic cautery procedures is desirable in order to stem bleeding. While both monopolar and bipolar endoscopic cautery instruments are known (such as disclosed in U.S. Pat. No. 4,418,692 to Guay), increasingly, bipolar cautery is preferred because it is less traumatic to the patient. In bipolar cautery instruments, the electric current path is from one electrode, through the tissue to be cauterized, and then through to the other electrode and out the instrument. Thus, only that tissue between the two electrodes is being cauterized. On the other hand, in monopolar instruments, the patient effectively becomes the second electrode, and the current must be dissipated through the patient. Thus, control of the cautery location is not exact, and tissue surrounding the tissue to be cauterized is also subject to different degrees of cautery.
In U.S. Pat. No. 4,763,660 to Jaeger, a bipolar endoscopic microelectrocautery device is shown. The Jaeger device also discloses a device for obtaining biopsies. However, the device disclosed in Jaeger requires a number of different single function "instrument heads" only one of which may be attached at any time to the instrument for performing a specific function such as grasping, cutting, or cauterizing. Thus, the biopsy forceps "head", is incapable of cauterizing, while the cauterizing "head" is incapable of obtaining a biopsy. This arrangement still does not permit the surgeon to cauterize at the biopsy site at the time of taking a biopsy.